A006360 Antichains (or order ideals) in the poset 2*2*3*n or size of the distributive lattice J(2*2*3*n).
1, 50, 887, 8790, 59542, 307960, 1301610, 4701698, 14975675, 43025762, 113414717, 277904900, 639562508, 1393844960, 2896063220, 5768600412, 11066514565, 20526933442, 36936277875, 64660182026, 110394412610
Offset: 0
References
- J. Berman and P. Koehler, Cardinalities of finite distributive lattices, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), 103-124.
- Manfred Goebel, Rewriting Techniques and Degree Bounds for Higher Order Symmetric Polynomials, Applicable Algebra in Engineering, Communication and Computing (AAECC), Volume 9, Issue 6 (1999), 559-573.
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
Links
- J. Berman and P. Koehler, Cardinalities of finite distributive lattices, Mitteilungen aus dem Mathematischen Seminar Giessen, 121 (1976), 103-124. [Annotated scanned copy]
- G. Kreweras, Les préordres totaux compatibles avec un ordre partiel, Math. Sci. Humaines No. 53 (1976), 5-30.
- Feihu Liu, Guoce Xin, and Chen Zhang, Ehrhart Polynomials of Order Polytopes: Interpreting Combinatorial Sequences on the OEIS, arXiv:2412.18744 [math.CO], 2024. See p. 9.
- Index entries for sequences related to posets.
Crossrefs
Formula
Empirical G.f.: (x+1)*(x^6+36*x^5+279*x^4+594*x^3+279*x^2+36*x+1)/(1-x)^13. - Colin Barker, May 29 2012
Extensions
More terms from Mitch Harris, Jul 16 2000